The present invention relates to a cooling system and method for cooling high heat dissipating components within electronic and computer system enclosures. More particularly, this invention relates to a cooling system for removing heat from high heat dissipating components located within portable electronic and computer devices having a main body portion and a cover connected in an openable manner to the main body portion.
High heat dissipating components located within small confines of certain consumer electronic devices may create hot spots at certain locations along the external casing of the device. These hot spots may be uncomfortable to the touch, and in some cases may cause injury. Therefore, it is desirable to dissipate heat away from the high heat generating components located within the enclosure of small form factor devices in such a way as to keep the internal components within their specified operating temperature range and to preclude the creation of hot spots along the exterior of the enclosure, and particularly along the bottom of the enclosure.
A number of prior techniques have been used to remove heat from heat generating components located within the confines of a computer system enclosure. For example, cooling integrated circuit devices within notebook computers has evolved from the simple attachment of a finned heat sink to the top surface of the device, to the development of finned heat sinks having integral fans. More recent developments have included the use of forced cooling air to cool one side of a heat spreading plate having an integrated circuit attached to the other side. Although these heat transfer methods have proved sufficient in the past, they do not provide the heat removal capacity and/or efficiency needed to cool current and future high-performance microprocessors in portable general-purpose computers and other thin profile electronic devices.
What is needed then is an apparatus and method which solves the aforementioned problems associated with cooling internal electronic circuits located within portable consumer electronic and computer devices. Particularly, what is needed is a highly efficient cooling system that is conformable to the size and power consumption restrictions imposed by small form factor and thin profile electronic devices, such as, for example, notebook computers.
Briefly described, provided herein in one aspect is a cooling system for a portable electronic device, such as a portable computer, which includes a computer body having a heat generating electronic element therein, and a display section having a screen connected in an openable manner to the computer body. The cooling system includes a cold plate assembly and a heat exchange assembly. The cold plate assembly has a surface coupled to the heat generating electronic element for extraction of heat generated thereby, and the heat exchange assembly is disposed within the openable display section of the portable computer. The heat exchange assembly includes a hollow channel for carrying coolant. A conduit is provided for carrying coolant between the cold plate assembly and the hollow channel of the heat exchange structure; and a circulation pump is also provided for circulating coolant therethrough. Specifically, the circulation pump circulates coolant between the cold plate assembly and the heat exchange assembly in a manner so as to cause heat from the heat generating electronic element to be transferred to the coolant, and carried by the coolant to the heat exchange assembly for dissipation therefrom. The heat exchange assembly further includes a thermally conductive plate and air-cooled fins. The hollow channel is coupled to one main surface of the thermally conductive plate for facilitating the transfer of heat from coolant within the channel to the plate, and the air-cooled fins are coupled to an opposite main surface of the thermally conductive plate for facilitating the dissipation of heat transferred to the thermally conductive plate.
In another aspect, an electronic apparatus is provided which includes a base housing having a heat-generating component disposed therein, and a lid housing supported on the base housing for movement relative thereto between open and closed positions. A cooling system is also provided for dissipating operating heat generated by the heat-generating component. The cooling system includes a cold plate assembly having a surface coupled to the heat-generating component, and a heat exchange assembly disposed within the lid housing. The heat exchange assembly includes a hollow channel for carrying coolant. A conduit carries coolant between the cold plate assembly and the hollow channel within the heat exchange assembly. A circulation pump is provided for circulating coolant through the conduit between the cold plate assembly and the heat exchange assembly in a manner to cause heat from the heat-generating component to be transferred to the coolant, and carried by the coolant to the heat exchange assembly for dissipation therefrom. The heat exchange assembly further includes a thermally conductive plate and air-cooled fins. The hollow channel is coupled to one main surface of the thermally conductive plate for facilitating the transfer of heat from coolant within the hollow channel to the thermally conductive plate, and the air-cooled fins are coupled to an opposite main surface of the thermally conductive plate for facilitating the dissipation of heat transferred to the thermally conductive plate from coolant within the hollow channel.
In a further aspect, a method of fabricating a cooling system is provided for a portable computer which includes a computer body having a heat-generating electronic element, and a display section with a screen connected in an openable manner to the computer body. The method includes: coupling a cold plate assembly to the heat-generating electronic element; disposing a heat exchange assembly within the openable display section of the portable computer, the heat exchange assembly including a hollow channel for carrying coolant; providing a conduit for carrying coolant between the cold plate assembly and the hollow channel within the heat exchange assembly; disposing a circulation pump in the computer body for circulating coolant through the conduit between the cold plate assembly and the heat exchange assembly in a manner causing heat from the heat-generating electronic element to be transferred to the coolant, and carried by the coolant to the heat exchange assembly for dissipation therefrom; and providing the heat exchange assembly with a thermally conductive plate and air cooled fins, the hollow channel being coupled to the thermally conductive plate for facilitating the transfer of heat from coolant within the hollow channel to the thermally conductive plate, and the air-cooled fins being coupled to the thermally conductive plate for facilitating the dissipation of heat transferred to the thermally conductive plate from coolant within the hollow channel.
Advantageously, provided herein is a liquid-to-air cooling system which significantly increases the cooling capacity of a portable computer. This allows a heat-generating component, such as a microprocessor disposed within the body of the portable computer, to either run at a faster rate, or for a given component, allows the portable computer environment to run cooler, thereby extending reliability. In one embodiment, a water-to-air cooling system is described which employs forced water flow to provide a significantly lower thermal resistance path from, for example, a processor module in the body of a portable computer to a heat exchange assembly disposed within the openable cover. A folded fin structure can be employed within the heat exchange assembly to provide increased surface area for heat transfer. The higher heat transfer coefficient provided by forcing air flow through the air-cooled fins results in a significantly lower thermal resistance path for heat within coolant passing through the heat exchange assembly to ambient air. Further, an auxiliary thermal path is created in one aspect from the heat exchange assembly directly to the back wall of the cover via thermal conduction. Thus, in the event that the air moving device malfunctions, the portable computer could still operate at reduced power via natural convection and radiation off the cover. Still further, by dissipating heat away from the high heat-generating component(s) disposed within the body of the portable computer, the components are more readily maintained within their specified operating temperature range, and the creation of hot spots along the exterior of the portable computer is precluded.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.